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    <title>Document</title>
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        }

        ul {
            float: left;
            background-color: aqua;
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        .box {
            float: right;
            width: 400px;
            height: 400px;
        }
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    <ul>
        <li><a target="main" href="./08-a.html">a.html</a></li>
        <li><a target="main" href="./09-b.html">b.html</a></li>
        <li><a target="main" href="./10-c.html">c.html</a></li>
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